1. Field of the Invention
The present invention relates to a dry cleaner for wafer carriers used in a semiconductor manufacturing system, and more particularly, to a dry cleaner in which gas is sprayed simultaneously into a carrier box and a cover of a wafer carrier by a plurality of spray means, and by which particles that are adhered to the interior surface of the wafer carrier can be easily eliminated.
2. Description of the Related Art
A wafer carrier is a container, including a carrier box and a cover, for moving wafers in the course of a process for manufacturing semiconductor devices. When the manufacturing process is not be carried out, for example, when the wafers are being held for further processing at a later time, the wafers are stored in the carrier box and sealed with the cover.
With the rapid progress of automation, larger wafer capacity, and high integration of the semiconductor devices, more attention has been paid to the wafer carrier including the carrier box and the cover.
Such increased attention has been a result of two main factors. First, there must be compatibility between the wafer carriers and the robot manufacturing systems required for the automated processes, and second, contamination of the wafers must be prevented by the wafer carriers.
In particular, the second contamination problem plays an important role in the degradation of the semiconductor devices. That is, broken wafer pieces or fine wafer particles may be generated due to an impact or friction between the carrier boxes or the carrier box and the wafers. Such contaminants adhere to the wafers, thereby causing degradation of the semiconductor devices.
Further, organic and metallic contamination caused by outgassing from the material of the carrier box may be a latent source for polluting the wafers stored in the carrier box, thereby deteriorating the yield and reliability of the semiconductor devices.
Generally, to solve the above problems, the wafer carrier is cleaned, mainly by wet cleaning, to prevent contamination of the wafer carrier. However, such a wet cleaning process requires a large cleaning system and much time to perform the task. Moreover, further contamination may arise due to the cleaning solution itself.
In addition to the wet cleaning method, other cleaning methods have utilized a vacuum tube. However, the vacuum tube method also has a shortcoming in that much time is required for the cleaning process.